/*
 *  Copyright 2007 Blandware (http://www.blandware.com)
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package com.blandware.atleap.webapp.action.core.sequence;

import com.blandware.atleap.common.Constants;
import com.blandware.atleap.model.core.ActionPage;
import com.blandware.atleap.model.core.Layout;
import com.blandware.atleap.model.core.Localizable;
import com.blandware.atleap.model.core.Page;
import com.blandware.atleap.model.core.Sequence;
import com.blandware.atleap.service.core.SequenceManager;
import com.blandware.atleap.webapp.action.core.BaseAction;
import com.blandware.atleap.webapp.form.core.SequenceForm;
import com.blandware.atleap.webapp.util.core.CacheUtil;
import com.blandware.atleap.webapp.util.core.WebappConstants;
import com.blandware.atleap.webapp.util.core.WebappUtil;
import org.apache.commons.validator.GenericValidator;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.action.ActionMessages;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.util.Set;

/**
 * <p>Deletes sequence.
 * </p>
 * <p><a href="DeleteSequenceAction.java.html"><i>View Source</i></a></p>
 * <p/>
 *
 * @author Roman Puchkovskiy <a href="mailto:roman.puchkovskiy@blandware.com">
 *         &lt;roman.puchkovskiy@blandware.com&gt;</a>
 * @version : $Revision: 1.4 $ : 2007/12/17 13:38:25 $
 * @struts.action path="/core/sequence/delete"
 * name="sequenceForm"
 * scope="request"
 * validate="false"
 * roles="core-sequence-delete, core-sequence-deleteOverriden"
 * @struts.action-forward name="listSequences"
 * path="/core/sequence/list.do"
 * redirect="false"
 */
public final class DeleteSequenceAction extends BaseAction {
	/**
	 * @param mapping  The ActionMapping used to select this instance
	 * @param form     The optional ActionForm bean for this request (if any)
	 * @param request  The HTTP request we are proceeding
	 * @param response The HTTP response we are creating
	 * @return an ActionForward instance describing where and how
	 *         control should be forwarded, or null if response
	 *         has already been completed
	 */
	public ActionForward execute(ActionMapping mapping, ActionForm form,
	                             HttpServletRequest request, HttpServletResponse response) throws Exception {

        HttpSession session = request.getSession();
        SequenceForm sequenceForm = (SequenceForm) form;

        Long ownerId;
		if ( !GenericValidator.isBlankOrNull(sequenceForm.getOwnerId()) ) {
			ownerId = Long.valueOf(sequenceForm.getOwnerId());
		} else {
			if ( log.isWarnEnabled() ) {
				log.warn("Missing owner ID. Returning to index...");
			}
            return mapping.findForward("admin");
		}

        session.setAttribute(WebappConstants.OWNER_ID_KEY, ownerId);

		Long sequenceId;
		if ( !GenericValidator.isBlankOrNull(sequenceForm.getId()) ) {
			sequenceId = Long.valueOf(sequenceForm.getId());
		} else {
			if ( log.isWarnEnabled() ) {
				log.warn("Missing sequence ID. Returning to list...");
			}
            return mapping.findForward("listSequences");
		}

		SequenceManager sequenceManager = (SequenceManager) getBean(Constants.SEQUENCE_MANAGER_BEAN);
		Sequence sequence = sequenceManager.retrieveSequence(sequenceId);

		if ( sequence == null ) {
			// sequence not found. it might be deleted by someone else
			ActionMessages errors = new ActionMessages();
			errors.add("sequenceNotFound", new ActionMessage("core.sequence.errors.notFound"));
			saveErrors(request, errors);
            return mapping.findForward("listSequences");
		}

		Localizable owner = sequence.getOwner();
		if ( owner instanceof Layout && !request.isUserInRole("core-sequence-delete") ) {

			String sequenceIdentifier = sequence.getIdentifier();

            Set identifiers = WebappUtil.getOverridableSequenceIdentifiers(owner,  request);
            boolean overridable = identifiers.contains(sequenceIdentifier);

			if ( !overridable ) {
				ActionMessages errors = new ActionMessages();
				errors.add("sequenceCannotDelete", new ActionMessage("core.sequence.errors.notOverriden.cannotDelete"));
				saveErrors(request, errors);
                return mapping.findForward("listSequences");
			}
		}

        // Forbid to delete sequence from action page if this sequence is not a
        // "redifinition" and user has no rights to delete sequences
        if (owner instanceof ActionPage && !request.isUserInRole("core-sequence-delete")) {
            Set identifiers = WebappUtil.getOverridableSequenceIdentifiers(owner, request);
            String identifier = sequence.getIdentifier();
			boolean canDelete = identifiers != null && !identifiers.isEmpty() && identifiers.contains(identifier);
            if (!canDelete) {
				ActionMessages errors = new ActionMessages();
				errors.add("sequenceCannotDelete", new ActionMessage("core.sequence.errors.actionPageSequence.cannotDelete"));
				saveErrors(request, errors);
                return mapping.findForward("listSequences");
            }
        }

		sequenceManager.deleteSequence(sequenceId);

        CacheUtil cacheUtil = CacheUtil.getInstance(request);
        if (owner instanceof Layout) {
            Layout layout = (Layout) owner;
            cacheUtil.flushLayoutSequenceCache(layout.getDefinition());
        } else if (owner instanceof Page) {
            Page page = (Page) owner;
            cacheUtil.flushPageSequenceCache(page.getUri(), sequence.getIdentifier());
        }

        session.setAttribute(WebappConstants.OWNER_ID_KEY, ownerId);
        return mapping.findForward("listSequences");
	}
}